Phone calling by itself?

today my boyfriend and I were sitting next to each other. His phone started ringing in his pocket.He looked up at me weird because on his cell was my number calling, We figured maybe we were sitting on my phone. Turns out my phone was in the hall on a table. This has happened through out the day. I thought maybe the phones were glitched and just calling the last numbers called, but we both have talked to other people on our phones today more than once. We both have recieved about 12 calls today from each other without us doing the calling ourselves. One time we were even driving and his phone called mine even though his phone was at home on the table.Anyone heard of this?The phone company has never heard of this.